The use of optical fibers in 3D printing technology is known in the art. WO2015/077262, for instance, describes 3D printer inputs including filaments comprising separated layers or sections. These inputs particularly including filaments may be prepared by coextrusion, microlayer coextrusion or multicomponent/fractal coextrusion. These inputs, and specifically filaments, are alleged to enable layering or combining different materials simultaneously through one or more nozzles during the so-called 3D printing process. These techniques facilitate smaller layer sizes (milli, micro, and nano) different layer configurations as well as the potential to incorporate materials that would otherwise not be usable in standard 3D printer methods. Amongst others, this document describes a substrate reinforced 3D filament where the substrate(s) is coiled braided, weaved, folded, stacked, etc. in such a way that when printed, the substrate will release with the length of the printed material. Substrates could include but are not limited to carbon fibers, optical fibers, Kevlar fibers and wires. Multiple substrates could be incorporated in the filament. It is necessary to stack weave or coil the fibers if the printed path is longer than the length of filament extruded to print that path.